Combining the light of four VLTs for the ESPRESSO instrument

This engineering rendering shows the front-end part of the ESPRESSO instrument on ESO’s Very Large Telescope at the Paranal Observatory in northern Chile. ESPRESSO will be an ultra-precise spectrograph that is capable of combining light from all four VLT Unit Telescopes to create a virtual 16-metre aperture telescope. This picture shows how the beams coming in from the four different telescopes enter the instrument before being fed to the main spectrograph.